Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds real value beyond that: no credentials/URLs consumed, entitlement stays 'unknown until checked', provider costs are never revealed, and unmapped assets plus cross-mode conflicts are surfaced rather than failing silently. Missing is what happens on an unmapped asset (hard error vs. advisory field in the response).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the read-only preflight purpose and scope before enumerating outputs and exclusions; nearly every clause carries distinct information (cross-mode conflicts, provenance, entitlement unknown, price-estimate applicability). Slightly dense and run-on, but no filler sentences.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, the description needn't enumerate return fields, and annotations cover the safety profile, so what remains is behavioral and scoping detail — all of which is provided. The uncovered parameters (family, values, canvas_project_id, requested_capability) are the only notable gap for a 6-parameter tool with nested assets.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 17%, so the description carries most of the burden. It clarifies that assets are hypothetical metadata mapped to technical slots and that durations combine across assets, which maps loosely to the assets array and its fields, but family, values, canvas_project_id and requested_capability are left unexplained in both schema and description. Partial compensation, not full.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('read-only per-file and aggregate preflight') scoped to 'ONE exact model and mode', and explicitly separates it from generate/upload/quote/submit/estimate siblings in the closing sentence. An agent can tell this apart from aimixer_estimate, aimixer_quote and aimixer_submit without inspecting either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Clear usage context: pass only declared hypothetical asset metadata, no URL/upload/credentials, and the negative list ('does not generate, upload, quote, approve, submit') implicitly routes agents to the write/quote siblings. It stops short of naming the alternative tools explicitly or stating prerequisites such as needing a catalog key first, so it is strong but not a full when/when-not map.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.